Carbon and method of manufacturing same.



rini'r s A% AT FI IQ.

CARBON AND METHOD OF MANUFACTURING SAME.

No Drawing.

To all whom it may concern Be it known that I, ROBERT D. PIKE, a citizen of the United States, residing at Richmond, in the county of Contra Costa and State of California, have invented certain new and useful Improvements in Carbons and Methods of ManufacturingSame, of which the following is a specification.

The present invention relates to electric light carbons, mainly designed for use as projector carbons, and the invention resides in the production of carbons for use generally from what is commonly known as lamp black refuse derived from the manufacture of illuminating gas from crude petroleum.

I have discovered that carbons produced from the so-called lamp black refuse from the manufacture of illuminating gas from crude petroleum possess certain qualities lacking in the ordinary carbons, noticeably the ability of the carbons to be carried very close together while burning and even to-be frozen, Without hissing. This is a feature which no other carbon possesses, and its ad: vantage is two fold. First, carbons give a greater luminous efiiciency when carried close with a hort arc, and secondly, it is much easier for the operator to adjust the carbons when displaying a picture if he is not called on to be continuously guarding against hissing. Again, the carbons produced from the so-called lamp black refuse of the gas plant have a higher current carrying capacity than the carbons as ordinarily made and employed for use in projecting machines, as,'for example, I can employ a 5 carbon to carry from sixty to seventy amperes, while with the ordinary carbon a *2" carbon is required for the carrying of a similar current.

I have found that the so-called lamp black refuse from the manufacture of illuminating gas from crude petroleum, per hundred pounds contains the following in about the proportion given 7 Three pounds of soluble and insoluble ash, of which two and one half pounds is soluble; tar, thirty pounds; hydrocarbons, soluble at low temperature, ten pounds; water, thirty pounds; lamp black, twenty-seven pounds.

In carrying out my process for the manufacture of the carbons from the mentioned lamp black, the first of the impurities to be eliminated is the tar.

For this purpose the mass of refuse matter Specification of Letters Patent.

Application filed December 21, 1915.

Patented Apr. 9, 1918.

Serial No. 68,088.

is subjected to hot water washing and milling in what is known as a chaser mill or wet pan. This operation, which is carried on for a period of approximately twenty minutes agglomerates the tar into pellets about the size of a pea and fiat Wafers, which are separated by Washing in a screen of suitable mesh. The resultant product is finely divided lamp black, which is treated for the elimination of soluble ash by any suitable washing apparatus, wherein the washing is done With successive charges of water, each charge being drained off for wa hing away the soluble ash. The material with the soluble ash eliminated therefrom is treated in a roaster or drier, wherein it is agitated while subjected to a temperature of approximately 1000 degrees Fahr., for the removal of all moisture and the high volatile hydrocarbons. This roasting is continued for approximately three hours, after which the material is ,in a dry powdered form, but

still contains a trace of hydrocarbon volatiles and from five to ten per cent. by weight of occluded air. To eliminate these features, the material is then charged in fire clay muffle and subjected to a bright red heat at a temperature of between 1800 degrees to 2000 degrees Fahr., and subjected to such roasting for eighteen hours.

The resultant product is lamp black, containing approximately one per cent. of volatile matter and one and one-half per cent. of insoluble ash.

After the material has become cool it is ground in a suitable mill and reduced to a fine powder, which is run through separators to remove iron particles which may be contained therein. A suitable flux is then added for the small per cent. of insoluble ash remaining therein, and thereafter, by the intermixing therewith of a small quantity of coal tar, the mixture is run through uitable rolls to produce a plastic body, which is then compressed into cylindrical cakes. These cakes are formed into green carbon sticks, which are baked in the usual manner for forming carbons.

The carbons produced from the so-called lamp black refuse of the plants manufacturing illuminating gas from crude oil have proved to be more eificient than the carbons 'is claimed as new and desired to be protected by Letters Patent 1S 1. The method of purifying the lamp black refuse derived from the manufacture of illuminating gas from crude oil, which consists first in eliminating therefrom by Washing the tar contained therein, then by washing removing the soluble ash, then roasting under agitation for the removal of moisture and the high volatile hydrocarbons, and then roasting at a higher temperature for the elimination of remaining hydrocarbons.

2. The method of purifying the lamp black refuse derived from the manufacture of illuminating gas from crude, oil, which consists first in eliminating from the material by washing and roasting the impurities contained therein, nd then reducing the material to a owder form.

In testimony whereof I have signed my name of this specification in the presence of tWo subscribing witnesses.

ROBERT D. PIKE. Witnesses:

C. F. Lnmsmr, W. H. CONN. 

